The Impact of Electronic Learning Package in Mathematics for Secondary Schools in Palestine on Students’ Achievement Amidst the COVID-19 Pandemic

The study aimed to design an electronic learning package to be delivered through the Internet and mobile phones to support students’ self-learning in mathematics for secondary schools, especially the scientific stream in Palestine. The major objective of this package is to raise their academic achievement in the course of the COVID-19 pandemic. The study also aimed at investigating the impact of the e-learning package on improving the students’ academic achievement in math. To achieve these objectives, a constructivist and experimental approach was used as it suits the nature of the study. The sample consisted of 82 male and female students who were randomly divided into an experimental group of 42 male and female students and a control group of 40 male and female students. The study tools included an e-learning package that covered the fifth unit of math in the secondary school/ scientific stream entitled Definite Integration and Its Applications, and an achievement test to measure the students’ academic achievement. The findings of the study revealed the following: a statistically significant effect of using the e-learning package on the students’ academic achievement during the pandemic with a huge effect, a statistically significant difference between the average achievement scores of the experimental group and the control group due to gender, and an interaction between the method of education and gender

Conceptual design of cantilever support for long haul bus passenger seat

This paper describes the conceptual design of cantilever support for long haul bus passenger seat. The advantages of cantilever bus seat structure is light weight, the luggage can be put under the seat and it is easy for floor cleanup. The total design technique was used to develop the cantilever support. Market survey was conducted to study on current available cantilever supported vehicle seat. After that, product requirement of cantilever design is defined. Next, brainstorming technique was used to generate the preliminary concept of cantilever design. Six conceptual designs were generated for selection. The matrix evaluation method was used to determine the final design of cantilever design. The weight of the concept was obtained through weighted analysis. Lastly, the final concept will be fabricated as prototype for further validation purpose

Disposal Options of Bamboo Fabric-Reinforced Poly(Lactic) Acid Composites for Sustainable Packaging: Biodegradability and Recyclability

The present study was conducted to determine the recyclability and biodegradability of bamboo fabric-reinforced poly(lactic) acid (BF-PLA) composites for sustainable packaging. BF-PLA composite was recycled through the granulation, extrusion, pelletization and injection processes. Subsequently, mechanical properties (tensile, flexural and impact strength), thermal stability and the morphological appearance of recycled BF-PLA composites were determined and compared to BF-PLA composite (initial materials) and virgin PLA. It was observed that the BF-PLA composites had the adequate mechanical rigidity and thermal stability to be recycled and reused. Moreover, the biodegradability of BF-PLA composite was evaluated in controlled and real composting conditions, and the rate of biodegradability of BF-PLA composites was compared to the virgin PLA. Morphological and thermal characteristics of the biodegradable BF-PLA and virgin PLA were obtained by using environment scanning electron microscopy (ESEM) and differential scanning calorimetry (DSC), respectively. The first order decay rate was found to be 0.0278 and 0.0151 day�1 in a controlled composting condition and 0.0008 and 0.0009 day�1 in real composting conditions for virgin PLA and BF-PLA composite, respectively. Results indicate that the reinforcement of bamboo fabric in PLA matrix minimizes the degradation rate of BF-PLA composite. Thus, BF-PLA composite has the potential to be used in product packaging for providing sustainable packaging

Optimization of Key Parameters Towards High Performance Perovskite Solar Cells

Here, we report important findings regarding underestimated parameters for the synthesis and fabrication of high-performance perovskite solar cells. These parameters include the effect of Fluorine-doped Tin Oxide (FTO) etching, FTO cleaning, the number of compact TiO 2 (c-TiO 2 ) layer, the number of mesoporous TiO 2 (m-TiO 2 ) layers and the aging time before Ag deposition. Our results demonstrated that etching of FTO substrate with Zn/HCl is an essential step and has a major effect on the solar cell's open circuit voltage (Voc), fill factor (FF) and power conversion efficiency (PCE). Furthermore, we demonstrate new and improved protocols for the complete cleaning of FTO substrates. Despite the use of sonication and plasma etching in previous cleaning techniques, SEM images clearly show black clouds in the samples, which may be due to residual Zn particles in the FTO grooves. Thus, a soft toothbrush was used with detergent before sonication to detach the remaining Zn particles. In addition, the optimum number of spin coated layers of compact and mesoporous TiO 2 precursors was investigated. We found that one mesoporous and two compact TiO 2 layers were required to obtain a homogenous pinhole-free compact layer. Consequently, we demonstrate that using these optimized device fabrication procedures, a high efficiency of 17.96% for 6 mol% Co 3+ -doped TiO 2 solar cells can be obtained in comparison to 16.98% for pristine TiO 2 -based cells. Such cells are particularly important for wearable applications that require a small area and a high energy

Graphene oxide and gold nanoparticle based dual platform with short DNA probe for the PCR free DNA biosensing using Surface Enhanced Raman Scattering (SERS)

Surface-enhanced Raman scattering (SERS) based DNA biosensors have considered as excellent, fast and ultrasensitive sensing technique which relies on the fingerprinting ability to produce molecule specific distinct spectra. Unlike conventional fluorescence based strategies SERS provides narrow spectral bandwidths, fluorescence quenching and multiplexing ability, and fitting attribute with short length probe DNA sequences. Herein, we report a novel and PCR free SERS based DNA detection strategy involving dual platforms and short DNA probes for the detection of endangered species, Malayan box turtle (MBT) (Cuora amboinensis). In this biosensing feature, the detection is based on the covalent linking of the two platforms involving graphene oxide-gold nanoparticles (GO-AuNPs) functionalized with capture probe 1 and gold nanoparticles (AuNPs) modified with capture probe 2 and Raman dye (Cy3) via hybridization with the corresponding target sequences. Coupling of the two platforms generates locally enhanced electromagnetic field ‘hot spot’, formed at the junctions and interstitial crevices of the nanostructures and consequently provide significant amplification of the SERS signal. Therefore, employing the two SERS active substrates and short-length probe DNA sequences, we have managed to improve the sensitivity of the biosensors to achieve a lowest limit of detection (LOD) as low as 10 fM. Furthermore, the fabricated biosensor exhibited sensitivity even for single nucleotide base-mismatch in the target DNA as well as showed excellent performance to discriminate closely related six non-target DNA sequences. Although the developed SERS biosensor would be an attractive platform for the authentication of MBT from diverse samples including forensic and/or archaeological specimens, it could have universal application for detecting gene specific biomarkers for many diseases including cancer

Patients’ Perspectives, Experiences, and Concerns With Perianal Fistulae:Insights From Online Targeted-Disease Forums

Background: Perianal fistulae can undermine physical, emotional, and social well-being in patients with Crohn’s disease and are challenging to manage. Social media offers a rich opportunity to gain an in-depth understanding of the impact of perianal fistulae on patients’ daily lives outside of controlled environments. In this study, we conducted social media analytics to examine patients’ experiences with perianal fistulae and assessed the impact of perianal fistulae on patients’ behavior and overall well-being. Methods: We used a mixed-method approach to examine 119 986 publicly available posts collected from 10 Crohn’s disease forums in the United States between January 01, 2010 and January 01, 2020. Discussions related to Crohn’s perianal fistulae were retrieved. We randomly selected 700 posts and qualitatively analyzed them using an inductive thematic approach. We then applied a latent Dirichlet allocation probabilistic topic model to explore themes in an unsupervised manner on the collection of 119 986 posts. Results: In the qualitative analysis, 5 major themes were identified: (1) burden of perianal fistula; (2) challenges associated with treatment; (3) online information seeking and sharing; (4) patient experiences with treatments; and (5) patients’ apprehension about treatments. In the quantitative analysis, the percentages of posts related to the major themes were (1) 20%, (2) 29%, (3) 66%, and (4) 28%, while the topic model did not identify theme 5. Conclusions: Social media reveals a dynamic range of themes governing patients’ perspectives and experiences with Crohn’s perianal fistulae. In addition to the biopsychosocial burden, patients frequently express dissatisfaction with current treatments and often struggle to navigate among available management options.</p

Dynamics of Tachyon and Phantom Field beyond the Inverse Square Potentials

We investigate the cosmological evolution of the tachyon and phantom-tachyon scalar field by considering the potential parameter $\Gamma$($=\frac{V V"}{V'^2}$) as a function of another potential parameter $\lambda$($=\frac{V'}{\kappa V^{3/2}}$), which correspondingly extends the analysis of the evolution of our universe from two-dimensional autonomous dynamical system to the three-dimension. It allows us to investigate the more general situation where the potential is not restricted to inverse square potential and .One result is that, apart from the inverse square potential, there are a large number of potentials which can give the scaling and dominant solution when the function $\Gamma(\lambda)$ equals $3/2$ for one or some values of $\lambda_{*}$ as well as the parameter $\lambda_{*}$ satisfies condition Eq.(18) or Eq.(19). We also find that for a class of different potentials the dynamics evolution of the universe are actually the same and therefore undistinguishable.Comment: 8 pages, no figure, accepted by The European Physical Journal C(2010), online first, http://www.springerlink.com/content/323417h708gun5g8/?p=dd373adf23b84743b523a3fa249d51c7&pi=

Modelling and simulation of 1.2 MWp tenaga suria brunei photovoltaic power plant

The energy demand in Brunei Darussalam will increase in near future. The renewable energy is one of the alternative energy sources that could satisfy the increasing energy demands. Brunei Darussalam depends heavily on fossil fuel to generate its electricity needs. Fossil fuels are depleted and the main source of pollution. Photovoltaic (PV) systems generate electricity directly from the sunlight without any emission of global warming gases, and the fuel is free. In order to optimize the performance of PV systems their operation should be well understood. In this paper, we present the modelling of a real 1.2 MWp photovoltaic system. The PV power plant is tied to the grid. The PV array, the DC/DC converter and the DC/AC inverter are modelled and implemented in Matlab/Simulink. The controller of the gridconnected inverter is modelled to achieve constant voltage, constant frequency and to be synchronized with the grid. The system is simulated under Brunei weather conditions and the results are acceptable

Green Composites Made of Bamboo Fabric and Poly (Lactic) Acid for Packaging Applications—A Review

Petroleum based thermoplastics are widely used in a range of applications, particularly in packaging. However, their usage has resulted in soaring pollutant emissions. Thus, researchers have been driven to seek environmentally friendly alternative packaging materials which are recyclable as well as biodegradable. Due to the excellent mechanical properties of natural fibres, they have been extensively used to reinforce biopolymers to produce biodegradable composites. A detailed understanding of the properties of such composite materials is vital for assessing their applicability to various products. The present review discusses several functional properties related to packaging applications in order to explore the potential of bamboo fibre fabric-poly (lactic) acid composites for packaging applications. Physical properties, heat deflection temperature, impact resistance, recyclability and biodegradability are important functional properties of packaging materials. In this review, we will also comprehensively discuss the chronological events and applications of natural fibre biopolymer composites

Technical and economic feasibility study of solar powered air conditioners in Brunei Darussalam

On daily basis, a huge amount of fossil fuel is being burnt which results in a substantial amount of greenhouse gasses being released into the atmosphere. Air conditioners are becoming more common and are a major strain on energy demands especially in tropical climate countries like Brunei Darussalam. The photovoltaic electricity is a clean and sustainable. In this paper, we present a techno-economic feasibility study for solar powered air conditioning system in Brunei Darussalam. Four alternatives are investigated, 1) the PV system supplies 50% of the loads, 2) the PV system supplies 75% of the loads, 3) the PV system supplies 100% of the loads, and finally 4) the PV system supplies 125% of the loads. Where in the last two case the excess electricity is sold to the grid. With 0.3$ feed-in tariff. The best alternative is the grid-connected PV system with 125% capacity factor which was chosen due to its short payback time period as well as high profit rate over the lifetime of the project